Lithium Side Effects
When you first start taking lithium, you may experience tiredness, thirst, urinating more frequently, drowsiness, weight gain or mildly shaking hands. As your body adjusts to lithium, these should go away, but if they continue or get worse, talk to your doctor and pharmacist as soon as possible.
Less common side effects can be serious. Tell your doctor immediately if you experience diarrhea, fever, dizziness, vomiting, confusion, blurred vision, slurred speech, severe trembling of the hands, or unsteady walking.
Some rare side effects can occur and you need to seek treatment promptly. These include seizures, swelling or pain in the joints, fainting, vision changes, pain or discoloration of the fingers and/or toes, cold hands and/or feet, or problems with your heartbeat, whether it be too fast, too slow, or irregular.
Although it is rare, some people do have a serious allergic reaction to lithium. Get immediate medical attention (go to the emergency room if necessary) if you have symptoms such as rash, severe dizziness, trouble breathing, or itching or swelling (especially of face, tongue and/or throat).
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist promptly or seek emergency medical treatment, depending on the severity.